Redmond, Wash.—Microsoft has launched one of its largest ad campaigns ever, sinking $300 million into ads that feature comedian Jerry Seinfeld and company founder Bill Gates, according to published reports.

The campaign was developed by Crispin Porter+Bogusky, Miami and Boulder, Colo. McCann Erickson remains on its agency roster, but Microsoft broke from the firm to work with Crispin, according to The Wall St. Journal.

The campaign is seen as a way to rebrand the company. Apple Corp.’s “Mac vs. PC” ads have dogged Microsoft, portraying its products as stodgy, hard to use and fraught with bugs and viruses.